韦尔加腔消失征对胎儿胼胝体发育不全的产前超声诊断价值

The value of the cavum vergae vanishing sign for prenatal ultrasound diagnosis of fetal agenesis of the corpus callosum

目的探讨韦尔加腔（CV）消失征对胎儿胼胝体发育不全（ACC）的产前超声诊断价值。方法选取经MRI或引产胎儿尸体锯剖证实的20~32孕周的ACC胎儿51例作为ACC组，并随机选取20~32孕周的健康胎儿80例作为对照组，观察透明隔腔（CSP）及CV的显示情况。结果ACC组完全型胼胝体发育不全（cACC）36例，部分型胼胝体发育不全（PACC）15例；51例ACC胎儿中经产前MRI证实43例，经出生后MRI证实8例。CSP和CV显示情况如下：①ACC组CSP消失率为70．6％（36／51），对照组为0（0／80），差异有统计学意义（χ^2=77．870，P=0．000）；②ACC组CV消失率为96．1％（49／51），对照组为1．2％（1／80），差异有统计学意义（χ^2=118．673，P=0．000）。ACC组中，CV消失征象与ACC发生的相关系数r=0．952，P=0．000；CSP消失征象与ACC发生的相关系数r=0．771，P=0．000。不同孕周（20～24周、25～28周及29～32周）AcC组与对照组CSP消失率及CV消失率差异均有统计学意义（P〈0．001）。结论CV消失征是胎儿ACC重要的间接征象，可快速从CSP水平横切面获得，是中孕期胎儿ACC的重要产前超声筛查线索。

Objective To explore the value of the cavum vergae vanishing sign for prenatal ultrasound diagnosis of fetal agenesis of the corpus callosum（ACC）. Methods Fifty-one cases of ACC of 20 - 32 gestational weeks were confirmed by MRI or induced fetal autopsy. A random selection of 80 normal fetuses of 20 - 32 gestational weeks were chosed as control group. The displays of the cavum septum pellucidum （CSP） and the cavum vergae（CV） in the two groups were observed. Results There were 36 cases of complete agenesis of the corpus callosum （CACC） and 15 cases of partial agenesis of the corpus callusom （PACC） in ACC group. In 51 ACC cases, 43 cases were confirmed by prenatal MRI, while 8 cases were confirmed by postnatal MRI. The comparison of display of CSP and CV between the ACC group and the health group was as follows： （1）CSP vanishing rate in ACC group was 70.6% （36/51）, meanwhile the disappearance rate of CSP in the health group was 0（0/80）, the difference between the two groups was statistically significant（χ^2 = 77. 870, P = 0. 000）. （2）CV vanishing rate in ACC group was 96.1 % （49/51）, meanwhile the disappearance rate of CV in the health group was 1.2% （1/80）, the difference between the two groups was statistically significant （χ^2 = 118. 673, P = 0. 000）. The correlation coefficient between the CV vanishing sign and the occurrence of ACC was 0.952 （P = 0.000）, while the correlation coefficient between the CSP vanishing sign and the occurrence of ACC was 0. 771 （ P = 0. 000）. There were significant differences in CSP disappearance rate and CV disappearance rate between ACC group and control group at different gestational weeks （20 - 24 weeks, 25 - 28 weeks and 29 - 32 weeks） （all P 〈0. 001）. Conclusions The cavum vergae vanishing sign, as an important indirect sign of fetal agenesis of the corpus callosum, can be obtained quickly from horizontal transverse section of the cavum septum pellucidum. During the middle pregnancy, it could be an important prenatal ultrasound screening clue for fetal agenesis of the corpus callosum.